1. Field of the Invention
The present invention relates to a device for measuring the transport torques and tensions of magnetic video tape record/reproduce units.
2. Description of the Prior Art
Prior to the present invention, there was no convenient means for measuring the transport torques and tensions of magnetic video tape record/reproduce units. Yet it is often desirable to make such measurements to determine if a video tape unit is operating properly to provide quality recording or reproducing without damaging the tape transported thereby. It is particularly important to make such measurements on video tape units because of the potential loss of not only expensive video tape but also of valuable programs that may be recorded thereon. Heretofore, such measurements were made on video tape units by placing tape reels from a typical video cassette cartridge on the reel drive shafts of a tape unit and then measuring the torques and tensions of the unit by attaching a spring scale to the end of the tape on the reels. Although such prior measurement method produced relatively accurate results, it required skill and experience beyond the average user's ability and was, therefore, usually performed only by trained service personnel. The present invention, in contrast to the above procedure, provides a measuring device that is highly convenient to employ and may be utilized by users having little or no instruction in making transport torque and tension measurements.
A device for measuring transport torques of magnetic tape audio cassette record/reproduce units has been employed in the past and includes a housing that is identical to that of a standard cassette. A single reel is disposed in the housing and is attached to a spring biased indicator needle, the movement of which provides an indication of the torque exerted on the reel of the device by a record/reproduce unit. Such device differs from the present invention in that it is not designed for employment in video record/reproduce units and, therefore, does not provide the capability of making the various measurements of tensions and torques that must be made to determine whether a video record/reproduce unit is operating with acceptable tensions and torques.